Extraction of zinc.



G. S. BRAND.

EXTRACTION 0F ZINC.

APPLIQATIDN FILED FEB.18, 1e10,

Patented July 5. 1910.

The ATEN orrren.

CHARLES SKINNER BRAND, OF TROON, SCOTLAND, ASSI GNOR TO BRANDS PURE SPELTER COMPANY, LIMITED, OF GLASGOW, SCOTLAND.

nx'r nncrron or ZINC.

Specification of Letters Patent.

Patented July 5, 1910.

To all whom it may concern:

Be it known that I, (hm inn-1s SKINNER Bruno, a subject ot the King of Great lh'itain and Ireland, residing at .llentincl; Drive, Troon, in the county Ayr, Scotland, have invented new and useful Improvements Relating to the Extraction of Zinc, (for which I have made ap ilication for a patent in Great,

Britain, No. 9,955, hearing date April 27th, I

1909,) of which the following" -s a specification.

In the process of distillatioit for the extraction of zinc a retort is used associated with a condenser, and in order to reduce the quantity of in'i mrities which may pass from the retort and be deposited inthe condenser with the 'zinc, provision has been made wherebythe vapors in passing from the retort to the condenser are caused to pass through a body of material located in What may be termed the; filtering urea. ..\p-

aratus of the type referred to, has in some terms comprised a retort of tubular 't'orination presenting at the front end a mouth open to the full extent of its bore, and a condenser has been associated therewith by introducing its rear end into the mouth of the retort, and as the rear end of the condenser is commonly of'materially less diam;

eter than the bore of the mouth of the retort it has been customary to effect a joint by letting, which results in partially insuletingthe condenser from the heated walls of the retort. In providing a filtering area in appliances of this type it has been the practice in one method to charge the rear end of the condenser with filtering material, and as the rear end projects but slightly into the retort, the'said material is practically insulated from the heated walls of the retort. In this formthe rear end of the condenser pipe may be fully open or, be formed with apertures. In other cases it has been proposed to form the rear end of the condenserwith a restricted aperture and to provide a. tube, charged with filtering material, adapted to be inserted and fit therein and arranged to project partly into and partly from the rear end of the condenser,

and filters. of this character have been constructed having a well formed in the base of the tube intended to retain lead intercepted by the filtering medium, In this as in the former case the filtering material is practically insulated from the heated walls of the retort.

A filter associated with the condenser in one or other of the manners hercinbefore described has been used, particularly in the treatment of zinc residuals, such as galvanizers dross and zinc, ashes, but/it, is found, in 'dealing with zinc ores, Australian zinc concentrates and the like, where a higl'ier retort temperature is needed, that the filtering medium associated with the condenser docs not act ellici'ently but it becomes choked or blocked, whereupon it is necessary to displace or rename the filtering medium and complete the process by allowing the vapors, subsequently given ofi', to pass' unfiltered to the condenser. It has also been suggested that filtering" material might be placed in the retort. itself at. a, position adjacent to the condenser or where the temperature is not high enough to prevent the arrested lead from falling down in the liquid form. This, however, although not impossible, is not very practicable owing to the ditliculty of packing and retaining the filtering material in position in the retort.

This invention relates to in'iprovements in the extraction of zinc, and particularly to the extraction of the metal from zinc ores;

and the object oi. the invention is to provide an improved form of filter comprising a cl'iarge'of material refractoify relative to the temperatures to which it. is subjected adapted to be readily inserted, suitably positioned and readily withdrawn, of sullieient capacity to intercept the constituents of the vapors, principally lead and other heavy vapors,

which it is desired to prevent from passing into'the condenser from the retort; at the satne time the improved filter may collect the intercepted lead vapors in a condensed form and prevent the return thereof to the retort, while -nu1int'aini iig freedom for the passage of the zinc vapors from the retort to the condenser throughout the whole process of distilling the charge of the retort.

According to this Invention a filter is pro:

vided comprising a hollow contaitier-charged with refractory material, which is extennally formed to fit or approxii-nately fit, or be readily vfitted within the bore of the retort, and adapted to be positioned at such a distance from the mouth thereof as tobe directly srbjected to the heat of the walls a tion of the container located below the aperv out through either of the end apertures may be of say approximatelysix inches. In

of the front portion of the retort heated by the furnace, whereby the filter is subjected to a temperature sufficient to prevent condensation or solidification of the zinc vapors passing through the filtering area, but by which the vapors to be intercepted are con densed. The container has end walls, and a well may be formed at the base, apertures in the end walls above the. well serving to permit the container to be charged with refractory material, preferably composed of small pieces of refractory material, such as broken clay retorts, pieces of silica brick, or material preferably of a silicious nature, or other material refractory relative to the temperatures to which it is subjected. The apertures in the end walls also permit the vapors from the retort to enter into the filtering area at the inner end of the container and to permit the issuing vapors to pass from it into the condenser at the outer end of the-container. A filter fitting the retort in this manner has the effect of retaining some of the heat so that there is a saving of fuel in heating the retort.

In the accompauymg drawin Figure 1 represents in sectional side elevation an'example of appliances embodving' the features of this invention. Fig.v l is a front view partly in section, Fig. 3 is a side sectional elevation and Fig, 4 is a back view partly in section of a container to be hereinafter described. r

Inthe drawings A designates the furnace heating area, -13 a retort, C a condenser, and I) a container. In the form illustrated the container D is of approximately elliptical cross-section and conforms externally tothe bore of the retort B. The container, which for example may be composed of fire clay, is provided with end walls D D", in the back wall D ,of which vapor admission apertures E are provided, and in the front wall an aperture E is' formed to serve as the exit for the zinc vapors, and which may be used for the insertion of the refractory material. By this formation the base porturesyE, E constitutes a well, G desi nates the charge of refractory material.

In the drawings the container is shown in its service position.- 'At the completion of the distillation of a charge, the filter is removed from the retort and the intercepted lead in a molten condition may be poured- In construction, the container is prefer. ablyof material length in order to provide a filtering area of sufficient capacity to deal with a whole charge, for example its length order that the charge may present sufficient surface for causing the condensation of the vapors to be intercepted, pieces of refractory material may be adopted approximating to a cubic inch or less in size. I

What I do claim as my invention, and desire to secure by Letters Patent, is

1. A furnace heated I'Uull't furnished with' a filter comprising a comainer, a charge of refractory material within .tncontainer, the container ap )roximately filling the bore of the retort anti the retort at a place toward. the front thereof-where the retortis directly heated by the furnace, substantially as set forth.

2. A furnace heated retort furnished with a filter comprising a container, :1 charge of refractory material within the container, the container approximately filling the boreof the retort and being situated entirely within the retort at-the front thereof where the retort is directly heated by the furnace, and formed capable of being readily introduced into, fitted within and removed from the retort, substantially as described.

3. A furnace heated retort furnished with a filter comprising a container, :1 well in the base of the container, 2. charge of refractory material within the container, the container being situated within and toward the front of the retortat a place where the retort is directly heated by the furnace, substantially as set forth.

4. A furnace heated retort furnished with a filter comprising a container, a well in the base of the container, a charge of refractory material within the container, the container being situated within and at the front of the retort at a place where the retort is directly heated by the furnace, andfformed capable of being readily introduced into, fitted within, and removed from the retort, substantially as described.

. 5. A furnace heated retort furnished with a filter comprising a container,a char e of small pieces of refractory material within the container, the container approximately filling the bore of the retort and being situated entirely within the retort at a place -toward the front thereof where the retort is directly heated by the furnace, substantially as set forth.

6. A furnace heated retort furnished with a filter comprising a container, at well in the base of' the container, 9. char e of small pieces of refractory material wit in the container, the container being situated within and toward the front of the retort at a place being situated entirely within where the retort is directly heated by the CHARLES SKINNER BRAND.

Witnesses: I J. ALFRED BREWER,

WM. C11. Coono. 

